It isn't intrinsic to OSM - OSM is just a collection of geodata; you can display anything you want at any scale at all. If MapInfo is using openstreetmap.org's default tiles (which are just one way of showing the geodata) but is unable to scale the tiles as you want, that sounds like a generic issue with MapInfo. It doesn't hurt to ask here but I imagine you'd have more luck on a MapInfo-specific forum or on http://gis.stackexchange.com/ .